Description
filter.d/wuftpd.conf in Fail2ban 0.8.3 uses an incorrect regular expression that allows remote attackers to cause a denial of service (forced authentication failures) via a crafted reverse-resolved DNS name (rhost) entry that contains a substring that is interpreted as an IP address, a different vulnerability than CVE-2007-4321.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | fail2ban | 0.8.3-2sid1 | — |
| Debian 13 | fail2ban | 0.8.3-2sid1 | — |
| Debian 12 | fail2ban | 0.8.3-2sid1 | — |
References
- 33890 third-party-advisory
- 33734 vdb-entry
- http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=514163